posix/src/condsignalsupp.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup POSIX_COND_VARS Condition Variables
0007  *
0008  * @brief Implements wake up version of the "signal" operation
0009  */
0010
0011 /*
0012  *  COPYRIGHT (c) 1989-2014.
0013  *  On-Line Applications Research Corporation (OAR).
0014  *
0015  * Redistribution and use in source and binary forms, with or without
0016  * modification, are permitted provided that the following conditions
0017  * are met:
0018  * 1. Redistributions of source code must retain the above copyright
0019  *    notice, this list of conditions and the following disclaimer.
0020  * 2. Redistributions in binary form must reproduce the above copyright
0021  *    notice, this list of conditions and the following disclaimer in the
0022  *    documentation and/or other materials provided with the distribution.
0023  *
0024  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0025  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0026  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0027  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0028  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0029  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0030  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0031  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0032  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0033  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0034  * POSSIBILITY OF SUCH DAMAGE.
0035  */
0036
0037 #ifdef HAVE_CONFIG_H
0038 #include "config.h"
0039 #endif
0040
0041 #include <rtems/posix/condimpl.h>
0042
0043 /*
0044  *  _POSIX_Condition_variables_Signal_support
0045  *
0046  *  A support routine which implements guts of the broadcast and single task
0047  *  wake up version of the "signal" operation.
0048  */
0049
0050 int _POSIX_Condition_variables_Signal_support(
0051   pthread_cond_t            *cond,
0052   bool                       is_broadcast
0053 )
0054 {
0055   POSIX_Condition_variables_Control *the_cond;
0056   unsigned long                      flags;
0057   Thread_queue_Context               queue_context;
0058
0059   the_cond = _POSIX_Condition_variables_Get( cond );
0060   POSIX_CONDITION_VARIABLES_VALIDATE_OBJECT( the_cond, flags );
0061   _Thread_queue_Context_initialize( &queue_context );
0062
0063   do {
0064     Thread_queue_Heads *heads;
0065
0066     _POSIX_Condition_variables_Acquire( the_cond, &queue_context );
0067
0068     heads = the_cond->Queue.Queue.heads;
0069
0070     if ( heads == NULL ) {
0071       the_cond->mutex = POSIX_CONDITION_VARIABLES_NO_MUTEX;
0072       _POSIX_Condition_variables_Release( the_cond, &queue_context );
0073
0074       return 0;
0075     }
0076
0077     _Thread_queue_Surrender_no_priority(
0078       &the_cond->Queue.Queue,
0079       heads,
0080       &queue_context,
0081       POSIX_CONDITION_VARIABLES_TQ_OPERATIONS
0082     );
0083   } while ( is_broadcast );
0084
0085   return 0;
0086 }